TTHM a3.2 Arrhythmia Day 9/2/15 (Tintinalli 12, 13, 22, 23, 35, 36, 122, 140)
10a ~ Peds Arrhythmias (Jones)
Tachy >> Brady, & MANY causes, consider congenital issues, postop issues, cardiomyopathy, fever, emotional agitation. FamHx: Brugada, longQT, HOCM…
Neonates: 10yo/Adult: 60-100 HR awake
1030 ~ Tachycardia (Rossettie) ~ see my lecture…
11a ~ Small Groups (Prasad, Lavoie)
CHF, Ao Stenosis, Aflutter, refractory until digoxin?!
Sinus Tachycardia… SVT, Tox? Onset sudden? Sudden resolution? (>Variability with sinus tach vs SVT very regular!) Rate 150? think of flutter!
1230 ~ Jr/Sr Session (Sarsfield/Lavoie)
Ventricular Tachycardia? Yes, but DDx SVT with aberrancy?
Capture beat is a pwave that captures to transiently interrupt VTach
Fusion beats are partially conducted, in between VTach & capture beat… no specific leads
Precordial Concordance rather than progression cw VTach
RBBB R’>R; while VTach R>R’.
Brugada Criteria & Josephson Signs ~ Tertiary Notch in VTach > LBBB, but CANNOT r/o VTach.
Old & heart disease likely VTach.
Young without prior heart disease unless known arrhythmia hx likely SVT…
Why differentiate? SVT with aberrancy +Adenosine may work… VTach +Adenosine less likely…
Shock if unstable, medication first if relatively stable…
Avoid Adenosine in WPW?! Cardiovert. Then consult for antidysrhythmic…
Cardioversion is always an appropriate option for unstable pt.
2010 guidelines recommend: Procainamide (2a, 75% conversion), Amiodarone (2b, 30% conversion), & Lidocaine (2b, 35% conversion) for chemical cardioversion of monomorphic VTach.
“Slow VTach” ~ Drugs/Tox, Cocaine, TCA, hyperKalemia, Digoxin Tox Accelerated Jct rhythm, CAREFUL c DRUGS! ~ can cause asystole… Na Bicarb may help c Na channel block…
Versed before shock? Fentanyl? Etomidate?(half RSI dose) …then shock…
130 ~ Atrial Fibrillation/Flutter (Silaban)
Flutter “sawtooth” pattern is classic/characteristic, various ratios
2p ~ Pacemakers/AICDs & PreExcitation (GJ)
WPW accessory pathways preexcitation & tachydysrhythmia,
V6 appearance with/without pacing & ischemia,
analogous to Sgarbossa’s criteria for ischemia in LBBB,
TC/TV Pacing: Buttons: On/Off, Rate, Output (mA), Amplitude (mV sense), via cordis catheter
R IJ or L subclav, down ~15 to 20cm to RV, & defib pads >10cm from AICD…
Paced & capture beats on EKG, Magnets in the trauma bay.
Paced, sense, & action of pacemaker (Atrial, Ventricular, Dual, Inhibit, Trigger)
(VVI vs DDD ~ Vent paced, Vent sense, Inhibit action… VS Dual paced, Dual sense, Dual Action) VVI can cause pacemaker syndrome, atrial contraction against closed mitral & tricuspid valves, so DDD generally preferred.
Magnet over pacer induces asynchronous pacing, over AICD deactivates sensing & shocking.
*Orthodromic (narrow), Antidromic (wide), & AF are ~ 3 different versions of preexcitation dysrhythmia.
Ao stenosis: syncope, angina, failure.
Procainamide ok for wide complex stable-ish tachycardia.
3p ~ Bradycardia (ERod)
*SA node dysfunction & blocks… PR interval can be delayed especial by Na channel block…
Bradycardia has problems with impulse formation & impulse conduction…
Formation: sinus dysrhythmia (ie. resp variation), sinus bradycardia, sick sinus syndrome
*AV nodal dysfunction… Junctional escape (40-60 typical)
*Ventricular… escape & AIVR (20-40 typical)
*1st degree ~ PR prolongation
*2nd degree ~ type 1 Wenckebach & type 2 Mobitz II. Mobitz II
*3rd degree ~ Complete Heart block (& Acc Jct Rhythm of Ventricular overdrive?)
Atropine & pacing 1st line
HyperKalemia can cause bradycardia
HypoThyroid? CCB/BB OD?
Sick Sinus Syndrome Spectrum… (TachyBrady is a subtype) ~ needs Cardiology for Pacer.